| author | haftmann |
| Tue, 10 Jul 2007 17:30:50 +0200 | |
| changeset 23709 | fd31da8f752a |
| parent 21404 | eb85850d3eb7 |
| child 25135 | 4f8176c940cf |
| permissions | -rw-r--r-- |
| 2570 | 1 |
(* $Id$ *) |
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theory Dagstuhl |
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imports Stream |
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begin |
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consts |
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y :: "'a" |
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definition |
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21404
eb85850d3eb7
more robust syntax for definition/abbreviation/notation;
wenzelm
parents:
19763
diff
changeset
|
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YS :: "'a stream" where |
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"YS = fix$(LAM x. y && x)" |
|
21404
eb85850d3eb7
more robust syntax for definition/abbreviation/notation;
wenzelm
parents:
19763
diff
changeset
|
13 |
|
|
eb85850d3eb7
more robust syntax for definition/abbreviation/notation;
wenzelm
parents:
19763
diff
changeset
|
14 |
definition |
|
eb85850d3eb7
more robust syntax for definition/abbreviation/notation;
wenzelm
parents:
19763
diff
changeset
|
15 |
YYS :: "'a stream" where |
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"YYS = fix$(LAM z. y && y && z)" |
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lemma YS_def2: "YS = y && YS" |
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apply (rule trans) |
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apply (rule fix_eq2) |
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apply (rule YS_def [THEN eq_reflection]) |
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apply (rule beta_cfun) |
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apply simp |
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done |
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lemma YYS_def2: "YYS = y && y && YYS" |
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apply (rule trans) |
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apply (rule fix_eq2) |
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apply (rule YYS_def [THEN eq_reflection]) |
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apply (rule beta_cfun) |
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apply simp |
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done |
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lemma lemma3: "YYS << y && YYS" |
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apply (rule YYS_def [THEN eq_reflection, THEN def_fix_ind]) |
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apply simp_all |
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apply (rule monofun_cfun_arg) |
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apply (rule monofun_cfun_arg) |
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apply assumption |
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done |
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lemma lemma4: "y && YYS << YYS" |
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apply (subst YYS_def2) |
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back |
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apply (rule monofun_cfun_arg) |
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apply (rule lemma3) |
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done |
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lemma lemma5: "y && YYS = YYS" |
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apply (rule antisym_less) |
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apply (rule lemma4) |
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apply (rule lemma3) |
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done |
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lemma wir_moel: "YS = YYS" |
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apply (rule stream.take_lemmas) |
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apply (induct_tac n) |
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apply (simp (no_asm) add: stream.rews) |
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apply (subst YS_def2) |
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apply (subst YYS_def2) |
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apply (simp add: stream.rews) |
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apply (rule lemma5 [symmetric, THEN subst]) |
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apply (rule refl) |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* Zweite L"osung: Bernhard Möller *) |
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(* statt Beweis von wir_moel "uber take_lemma beidseitige Inclusion *) |
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(* verwendet lemma5 *) |
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(* ------------------------------------------------------------------------ *) |
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lemma lemma6: "YYS << YS" |
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apply (unfold YYS_def) |
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apply (rule fix_least) |
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apply (subst beta_cfun) |
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apply (tactic "cont_tacR 1") |
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apply (simp add: YS_def2 [symmetric]) |
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done |
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lemma lemma7: "YS << YYS" |
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apply (rule YS_def [THEN eq_reflection, THEN def_fix_ind]) |
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apply simp_all |
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apply (subst lemma5 [symmetric]) |
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apply (erule monofun_cfun_arg) |
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done |
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lemma wir_moel': "YS = YYS" |
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apply (rule antisym_less) |
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apply (rule lemma7) |
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apply (rule lemma6) |
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done |
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end |